from abc import ABC, abstractmethod

# 抽象基类
class FlyBehavior(ABC):
    # 抽象方法
    @abstractmethod
    def fly(self):
        pass

class FlyWithWings(FlyBehavior):
    def fly(self) -> None:
        print("I'm flying")

class FlyNoWay(FlyBehavior):
    def fly(self) -> None:
        print("I can't fly")

class FlyRocketPowered(FlyBehavior):
    def fly(self) -> None:
        print("I'm fly with rocket!")